The present invention relates to fenceless control of animals, and more particularly, to a method of controlling livestock utilizing an electronic fence for sequentially applying an audio and electric stimuli to livestock.
Livestock such as cows, sheep, pigs, goats and horses are currently primarily controlled by ordinary barbed wire fencing. However, drawbacks to wire fencing are that it is expensive to install and expensive to maintain, as well as having undesirable aesthetic and ecological considerations. Therefore, it has been proposed to utilize remote wireless transmitters with a receiver attached to the animal for administering control stimuli to the animal as a substitute for ordinary wire fencing.
Adverse impacts of grazing animals on soils, vegetation, and water quality in riparian areas is a serious land management problem. There is a direct relationship between intensity of grazing in riparian zones and bacterial water quality. Similarly, sediment, turbidity, and water temperature can be adversely affected by grazing in riparian zones. Exclusion of livestock from riparian areas is the initial step being recommended to address the adverse impacts of grazing in riparian zones. To this end, corridor fencing of problem areas has been implemented in many places to keep animals from the stream. Although this has been shown to be an effective solution to the problem, there are many drawbacks to wire fencing that calls for a different approach to solving the problem. As noted above, corridor fences are expensive to construct, costly to maintain, and may be aesthetically unpleasing. Also, corridor fencing forces ranchers managing the livestock to seek alternative, sometimes more costly, ways to provide water to grazing animals. In addition, herding can be used effectively to manage livestock in riparian areas but this approach is labor intensive and costs prohibit broad application. Thus, both of these alternatives have the potential to create severe economic problems for the livestock industry.
Accordingly, a new management alternative to fencing for controlling livestock grazing, especially in riparian areas, has been developed. This approach involves fenceless livestock control that uses audio warning and electrical stimulus to achieve animal avoidance of desired exclusion areas, such as riparian zones. The basic concept of the technology is that livestock can be trained to respond to audio warning and electrical stimulation provided to the ear of an animal as it enters the zone of influence of a signal from a field transmitter installed in the area of desired exclusion. The field transmitter emits a continuous, coded signal of designated strength that narrowly defines an area from which animals are to be excluded. Animals grazing in the area wear an electronic ear tag containing a receiver, an audio warning emitter, and a device to produce a small electrical stimulus to the ear. If the animal ventures within the prescribed exclusion zone, i.e. within the area of influence of the field transmitter, the signal is detected by the receiver in the ear tag worn by the animal. The signal activates an audio/electrical stimulation sequence. The sequence consists of the modules in the ear tag providing in an audio warning followed by a pause and then an electrical stimulation to the ear of the animal. If the animal exits the exclusion zone and moves back into the grazing zone at any time during the sequence, no further stimuli are received and the sequence is terminated. However, if the animal remains within range of the field transmitter or continues to proceed toward the field transmitter, the signal from the transmitter is again received and the animal is provided with another audio/electrical stimulation sequence. Thus, if the animal exits the range of the field transmitter following any audio and/or electrical stimulation, no further stimuli are provided to the animal until it again enters the range of the field transmitter. A built-in safety device locks up the ear tag, i.e. prevents continued audio/electrical stimulus, after a predetermined number of audio/electrical stimuli cycles are received should the animal become disoriented or if the mechanism malfunctions. The ear tag may then be reactivated by an unlock transmitter which may be placed at a remote watering/salt/mineral facility or which may be contained within a portable hand held transmitter. The hand held unit enables a user to lock, unlock and stimulate ear tags as well as to test the signals emitting from the field and unlock transmitters.
The variable strength transmitter is designed to provide a continuous coded signal. Signal strength may be varied by a set of attenuators to provide precise control of field strength, typically from about 100 to about 500 feet from the field transmitter. Thus, the size of the desired exclusion area can be varied by modifying the signal strength. Multiple settings on a single transmitter provide flexibility in field applications. Each field transmitter transmits a digital stimulation code which must be compatible with the particular ear tag receiver or else no stimulation of the animal occurs. The transmission of the digital stimulation code is also randomized so that the likelihood of two transmitters interfering by transmitting at the same time, either on the same or different properties, is minimized.
The ear tag includes a flat base for mounting the receiver circuitry. The audio warning sound is provided by an emitter mounted near the top of the tag to provide closest proximity to the ear canal of the animal. Electrical stimulus is provided by electrodes that are integral with the ear tag mounting post such that at least two electrodes are in constant contact with the ear.
The stationary unlock transmitter is typically remotely placed near a watering/salt/mineral facility and is utilized to automatically unlock the ear tags of animals as they return to water or salt/mineral areas. This effectively creates an unlock zone so that if an animal had entered the exclusion zone and received the full set of audio/electrical stimuli sequences, the ear tag would be locked up and the animal would be free to graze at will. The purpose of the unlock transmitter is to reactivate those ear tags so that the animal cannot proceed again into the exclusion zone without again receiving the audio/electrical stimuli sequences.